1. Field of the Invention
The present invention deals with the certain novel esters which are prepared by the reaction of a guerbet alcohol and meadowfoam fatty, methyl ester or triglyceride. These materials are useful as cosmetic ingredients where outstanding liquidity, resistance to oxidation, and minimal taste and odor variation are required. This combination of properties make these compounds excellent candidates as additives to personal care products like skin care oils and lipsticks.
2. Description of the Art Practices
Guerbet alcohols have been known for many years. Over the years there have been a number of derivatives patented. U.S. Pat. No. 4,868,236 to O'Lenick discloses a guerbet citric ester and polymers thereof useful in plastic lubrication.
U.S. Pat. No. 4,425,458 to Lindner and O'Lenick teaches that specific guerbet esters can be used as polycarbonate lubricants.
The selection of an ester for use in pigmented products requires that there be a significant number of carbon atoms present to get the wetting and oily properties desired. Fatty esters of guerbet alcohols and saturated fatty acids results in the preparation of esters which are liquid but not sufficiently hydrophobic (that is they do not have enough carbon atoms present) or if there are enough carbon atoms present, the products are slushy or solid at ambient temperatures.
Selecting unsaturated acids, like oleic acid, to make guerbet esters results in the desired liquidity, but two additional problems are encountered, (a) there is not enough hydrophoblcity since the number of carbon atoms is limited to 18, and (b) the acid undergoes pronounced degradation in a process referred to as "rancidity", making them unacceptable for applications where odor and taste is an issue. The recent availability of meadowfoam oil, with it's 20 to 22 carbon atoms and the specific location of it's double bonds, and it's reaction with the regiospecific beta branch of guerbet alcohols results in the preparation high molecular weight liquid stable ester, acceptable for use in pigmented personal care applications, like make-up and lipstick.
None of the prior compounds possess the critical meadowfoam carboxy moiety combined with the guerbet linkage in the molecule. Molecules of the current invention have guerbet substitution patterns in the alcohol and the meadowfoam alkyl group in the acid portion of the molecule.